128 AMERICAN JOURNAL 



tion,) only in having the revolving ribs slightly less evident than 

 in the typical pupitta. In the deep suture, inflated whorls, 

 small internally striated umbilicus, depressed form and strong 

 lines of increase, it is paralleled by many of the two hundred 

 or more specimens of pupilla now before me. The ribs on the 

 upper whorls of injlata are quite as strong as in pupilla, and 

 the differences, though evident, are so slight and the variation 

 in members of this genus is so great, that I am of the opinion 

 that the two species are really extremes of one form and that 

 the name injlata is at most entitled to no more than varietal 

 rank. The variety salmonea, as shown long since by Dr. Cooper, 

 is simply the southern form of pupilla, and hardly distinguish- 

 able from it, even by differences of degree. 



The small amount of material upon which Dr. Carpenter has 

 founded so many specific names, has been so largely reenforced 

 of late that a considerable amount of consolidation is likely to 

 ensue. There are other cases which I might have touched upon, 

 but I have only done so when it seemed that no reasonable doubt 

 could exist in regard to the matter, and never without a careful 

 study and comparison of the original type specimens in connec- 

 tion with the large series of my own collecting, 



Margarita lirulata, (Cpr.) Dall. 



Margarita lirulata, Cpr., Suppl. Rep. Brit. As. p. 653, 1864. 



Proc. Phil. Acad. Sci. p. 61, 1865. 

 Margarita var. tenuiseulpta, Cpr., Rep. 1. c. and Proc. Phil. 



Acad. Nat. Sci. p. 61, 1865. 

 Margarita var. subelevata + obsoleta + conica, Cpr., Proc. 



Phil. 1. c. 1865. Rep. 1. c. 1864. 

 Margarita lirulata, Cpr., Suppl. Rep. Br. As. p. 653, 1864. 



Proc. Cal. Acad. Sci. iii, p. 157, 1866. 

 Gribbula optabilis, Cpr., Suppl. Rep. p. 653, Proc. Cal. Acad. 



Sci. iii, p. 214, 1865. 

 Gribbula' parcipicta, Cpr., Suppl. Rep. p. 653, 1864. 

 Gribbula funieulata, Cpr., 1. c. 

 Gribbula sueeincta, Cpr., 1. c. 

 ? Gribbula lacunata, Cpr., 1. c. 



San Diego to Sitka. 



After a careful study of the types of the above species, pre- 

 served in the Smithsonian Museum, and a comparison of hun- 

 dreds of specimens collected by Mr. Stearns and myself at Mon- 

 terey and elsewhere, I am compelled to the belief that they are 

 simply forms of one protean species. They are not even varie- 

 ties capable of diagnosis ; for, not only are the intermediate 



